From: Systematic review of the relation between smokeless tobacco and cancer in Europe and North America
 |  |  |  | Heterogeneity | ||
---|---|---|---|---|---|---|
Type of ST (region)a | Adjustments/restrictionsb | Number of estimates (RR/OR ids)c | Random-effects RR/OR (95% CI) | χ2 | I2 | P(χ2) |
Larynx cancer d | Â | Â | Â | Â | Â | Â |
Any | Overall data | 5 (2, 3, 6, 12, 16) | 1.43 (1.08–1.89) | 4.8 | 17.4 | 0.304 |
 | Smoking-adjusted | 2 (3, 16) | 1.34 (0.61–2.95) | 4.0 | 75.3 | 0.044 |
Any (USA) | Overall data | 4 (2, 3, 6, 12) | 1.56 (1.21–2.00) | 1.7 | 0.0 | 0.646 |
 | Smoking-adjusted | 1 (3) | 2.01 (1.15–3.51) | -- | -- | -- |
Snuff (Scandinavia) | Overall data | 1 (16) | 0.90 (0.50–1.50) | -- | -- | -- |
 | Smoking-adjusted | 1 (16) | 0.90 (0.50–1.50) | -- | -- | -- |
Nasal cancer e | Â | Â | Â | Â | Â | Â |
Any | Overall data | 2 (10, 11) | 1.14 (0.73–1.77) | 0.9 | 0.0 | 0.339 |